Bacteria offer new options to clean up oil spills

German researchers have described metabolic processes in two types of bacteria that might be used in the future to clean up oil spills.

The report, written by a team of researchers from the Helmholtz Centre for Environmental Research in Leipzig, has been published in the recent issue of Applied and Environmental Microbiology.

The research involved bacteria Alcanivorax boskumensis and Oleispira antarctica. Alcanivorax converts hydrocarbons effectively into fatty acids and locks them subsequently directly into its cell-membranes. Oleispira seems especially promising to tackle oil disaster at higher latitudes, due to its ability to perform in extremely low temperatures.

So far, chemicals have been widely used in clean-up operations to make oil more soluble to enable removing it from the water surface. The currently most common substance of this kind is Corexir, developed after the Exxon Valdez disaster in Alaska in 1989.

However, the scientific community has long been critical of this substance due to its detrimental effects on the environment and human health.

The team responsible for the recent discovery has been working in the framework of the BACSIN project, funded by the European Union, which looks for innovative, more environmentally friendly, alternatives to Corexir.

"One approach for example could be to stimulate oil-degrading bacteria in their growth or for example by making them easier to use by freeze-drying so that they can be sprayed more easily than powders over the oil slick", explained Hermann J. Heipieper, a Helmholtz Centre researcher.

"However, there are still lots of details that require fine-tuning before the day arrives when they can be used to combat damage from oil spills,” he said, stressing the precautionary principle should always be given priority.

The researchers have thus focused on hydrocarbon-degrading bacteria that live naturally in marine ecosystems. These micro-organism digest hydrocarbons present in their environment to obtain energy. However, the amount of these hydrocarbons the bacteria have naturally had to consume has always been far lower than in the case of man-made oil spills.

While present in balanced ecosystems only in limited quantities, the bacteria have the ability to proliferate quickly when they come in contact with crude oil.

The Helmholtz researchers are now not only trying to understand these bacteria better but also propose changes into their genetic information that could make them even more efficient.